The big gap up on heavy volume
What the market says
"A stock that gaps up 10% or more on huge volume has momentum: buy the open and ride it."
What the charts did
More of them gave some back the next session than on an ordinary day: 57% of 7,719 closed below the anchor, against 49% of ordinary days. Median next-session move -0.7%.
A week on, 43% were above the anchor, fewer than the 55% of ordinary days; median -1.6%, and the middle 80% ran from -26.2% to +14.7% (ordinary: -6.1% to +6.8%).
A month on, 42% were above the anchor, fewer than the 53% of ordinary days; median -3.3%, and the middle 80% ran from -41.4% to +25.0% (ordinary: -12.6% to +13.5%).
Three months on, 40% were above the anchor, fewer than the 54% of ordinary days; median -8.3%, and the middle 80% ran from -59.2% to +41.4% (ordinary: -19.9% to +24.8%).
A year on, 37% were above the anchor, fewer than the 56% of ordinary days; median -22.8%, and the middle 80% ran from -86.7% to +92.1% (ordinary: -38.2% to +58.2%).
The week after this pattern is 3.2 times as wide as an ordinary week. That spread, not the median, is what the pattern tells you.
| Raw move from the anchor close | Instances | Share above | Median | Middle 80% | Ordinary day: share above | Ordinary day: middle 80% |
|---|---|---|---|---|---|---|
| Next session | 7,719 | 43% | -0.7% | -15.2% to +9.4% | 51% | -3.0% to +2.9% |
| 1 week (5 sessions) | 7,703 | 43% | -1.6% | -26.2% to +14.7% | 55% | -6.1% to +6.8% |
| 1 month (21 sessions) | 7,637 | 42% | -3.3% | -41.4% to +25.0% | 53% | -12.6% to +13.5% |
| 3 months (63) | 7,240 | 40% | -8.3% | -59.2% to +41.4% | 54% | -19.9% to +24.8% |
| 6 months (126) | 6,662 | 38% | -14.4% | -73.6% to +58.3% | 55% | -27.6% to +35.7% |
| 1 year (252) | 5,831 | 37% | -22.8% | -86.7% to +92.1% | 56% | -38.2% to +58.2% |